Applicability of Nacelle Anemometer Measurements for Use in Turbine Power Performance Tests: Preprint

Collection of accurate wind speed data is one of the more problematic elements in conducting wind turbine power performance tests. IEC 61400-12 specifies meteorological tower placement between two and four rotor diameters upwind of the test turbine. However, use of an upwind meteorological tower can be difficult at some sites. In some cases, complex terrain near the turbine may make placement ofan upwind tower impossible. In addition, purchase and erection of a meteorological tower can be expensive, particularly as the hub height of large turbines increases. Because of these concerns, wind farm owners and turbine manufacturers have expressed interest in the use of turbine nacelle-mounted anemometers for collection of wind speed data. The U.S. Department of Energy (DOE)-Electric PowerResearch Institute (EPRI) Wind Turbine Verification Program (TVP) has performed data collection and power performance tests at wind energy facilities located in the United States. The purpose of this paper is to evaluate the data gathered from the Big Spring, Texas; Algona, Iowa; and Springview, Nebraska, facilities to determine whether a meaningful relationship can be derived betweenmeteorological-tower and nacelle-anemometer wind speed measurements for Vestas V47 and V66 turbines (Big Spring) and Enron Z-50 turbines (Algona and Springview).